#include <iostream>

using namespace std;
template<typename T> 
ostream& print(ostream& os, const T& t){
    return os << t << "\n"; 
}
template<typename T, typename... args> 
ostream& print(ostream& os, const T& t, const args&... rest){
    os << t << ",   ";
    // 加不加return 都行，最好加上，函数完整
    return print(os, rest...);
}

int main()
{
    char a = ':';
    size_t x{9};
    // cout << sizeof(size_t
    print(cout, 3, "sgsdjf", 3.9, x, sizeof(size_t), sizeof( long int), sizeof(double), sizeof(int*), a);
    // 3,   sgsdjf,   3.9,   9,   4,   4,   8,   4 上面的输出结果
    cout << (1<2? 2:4) << "\n";
    return 0;
}